Telephone alarm system

ABSTRACT

The invention concerns an alarm system for detecting abnormal or emergency conditions and reporting them in response to placement of a call to an associated telephone. The system comprises a circuit including two switch means one operable by a detector in response to an abnormal condition, and the other operable in response to a call placed to the telephone, so that no alarm signal is generated until a call is received. The system need not be incorporated into the telephone circuit, but can be a selfcontained unit that transmits an alarm signal via the telephone.

United States Patent [5 6] References Cited UNITED STATES PATENTS [72]lnventors DavidSherman 432 Lowell Ave.;

179/5 X 179/2 A 179/2 A m e u I: "m.% 83 m k ai Hum mim D .mh m ZCw m3794 566 999 a fin 902 m m 572 E 9 05 ,9 w 375 a 548 m ,3 233 P h t 0 bL S nu..9 mm 22 00 4S. n n e we M 91 .C o LW .11 mmmsi a ll mN w tl uR08JO o. d N m .l n Pwm a AFP Att0rneyRich & Ericson ABSTRACT: Theinvention concerns an alarm system for detecting abnormal or emergencyconditions and reporting them [54] TELEPHONE ALARM SYSTEM in response toplacement of a call to an associated telephone. The system comprises acircuit including two switch means 14 Claims, 7 Drawing F|gs. 1

one operable by a detector in response to an abnormal condition, and theother operable in response to a call placed to the telephone, so that noalarm signal is generated until a call is received. The system need notbe incorporated into the telephone circuit, but can be a self-containedunit that transmits an alarm signal via the telephonet SHMI A Field of 1.1] 2 O 5 55 it .lIl.

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flifor aze ys TELEPHONE ALARM SYSTEM BRIEF DESCRIPTION OF THE INVENTIONIt is the general object of this invention to provide an improved alarmsystem for detecting any abnormal or emergency condition at a remotelocation by telephone. More specific objects are to provide an improvedalarm system which is selfcontained and does not require incorporationinto the telephone system, which can be installed or moved easilywithout technical knowledge, which is adapted to report any physicalcondition which can be detected, which is compact and inexpensive, whichdoes not interfere with the normal use of the telephone, and which has along service life with a minimum maintenance requirement. Other objectsand advantages of the invention will appear as the following descriptionproceeds.

The improved alarm system is especially adapted for use by homeowners,for the purpose of checking on the security and safety of the home whenthe owner is absent. Various utilities can be checked, such as themaintenance of electrical power, heat, water and fuel supplies.Dangerous conditions, including flooding, freezing of water pipes,extinction of pilot lights in stoves and heaters, excess accumulationsof snow, and appliances inadvertently left in operation, can also bedetected. The owner has only to place a call to his home telephone; ifeverything is in good order, there will be no response, but theexistence of an abnormal condition produces a distinctive signal on thetelephone.

Another important use of the system is for checking by oil companies ofthe fuel levels in their customerstanks. The conventional practice hasbeen to estimate oil usage on the basis of prevailing temperatures; thisaffords only a rough approximation, and often leads to unnecessarilyfrequent delivery calls, or more importantly, to exhaustion of thecustomers tanks. The improved system can incorporate a tank leveldetector, so that an oil company can determine whether deliveries areneeded simply by calling its customers telephones.

A preferred embodiment of the invention includes a circuit having twoswitch means, one of which is operable by one or more detectors ortransducers arranged to monitor whatever physical conditions the usermay select. The second switching means is operated by a transducerresponsive to placement of a call to the telephone with which the alarmsystem is associated; this transducer may be a contact microphone or asound microphone responsive to the ringing of the telephone, or aninductive pickup responsive to the current flow in the telephone cable.Thus, the circuit is energized only when both switching means areoperated; an alarm signal is not initiated by the occurrence of anabnormal condition until a call is placed. This conserves power, andpermits the use of ordinary flashlight batteries for a power supply,which are readily available even in remote locations. The system doesnot require household current, which is subject to failure underemergency conditions.

The circuit also includes means for producing a signal to the caller.These means preferably comprise a motive means for raising the telephonereceiver from its cradle, and a speaker for generating a distinctivesound signal audible over the telephone. Raising the telephone from itscradle without an audible signal will also signal the caller that thecircuit has been activated, because the ringing will stop and thetelephone circuit will be completed. The ltiotive means may comprise aservomotor or solenoid, together with a pivoted lever which is placed onthe telephone cradle and extends between its arms under the receiver.The lever is pivotable by the motive means to raise the receiver fromits cradle, and then to lower it after the alann signal has beendelivered. A servomotor may drive the lever through a speed-reductiondrive and an escapement which moves the lever in intermittent steps. Theescapement introduces a time delay in the answering of a call so thatthe caller can more readily identify the alarm signal, and determinesthe length of the signal.

It is also possible to simulate the lifting of the receiver from thecradle electrically by incorporating a connection to the telephone wiresand a suitable switch.

The operation of the alarm system is terminated by a third switch meansafter a signal has been delivered. These means may be a commutatorswitch driven by the motive means to deenergize the system after a cycleof mechanical operation, or a time-delay relay. The latter is preferredif a sound-responsive microphone is used, to prevent recycling of thesystem by feedback of its own alarm signal. A contact microphone willnot respond to an alarm signal delivered by a loudspeaker, so that thereis no requirement to overcome recycling if this combination oftransducer and signalling device are used.

It may be desired to delay the operation of the system after a call isinitiated, to permit the homeowner to answer calls when at home withoutpossible interruption by the alarm system, so that it is not necessaryto remove the system from the telephone for normal use. Such a delaywould also allow other subscribers on a party line ample time to answertheir calls without interference from the alarm system. This functioncan be performed by a time-delay relay included in the circuit, or by amechanical device such as a dashpot or the escapement previouslydescribed.

DETAILED DESCRIPTION OF THE DRAWINGS AND PREFERRED EMBODIMENTS While thespecification concludes with claims particularly pointing out thesubject matter which we regard as our invention, it is believed that aclearer understanding may be gained from the following description ofpreferred embodiments thereof, referring to the accompanying drawings,in which:

FIG. I is a perspective view showing one form of the invention inoperative association with a conventional telephone;

FIG. 2 is a sectional view in side elevation;

FIG. 3 is a fragmentary sectional plan view of mechanical elements ofthe alarm system;

FIG. 4 is a sectional view taken along line 4-4 in FIG. 3, looking inthe direction of the arrows;

FIG. 5 is a sectional view taken along line 55 in FIG. 3, looking in thedirection of the arrows;

FIG. 6 is a circuit diagram of a form of the system usable with acontact microphone, shown with several illustrative types of conditiondetectors; and

FIG. 7 is a circuit diagram of another form of the system usable with asound microphone, and including means for delaying response of thesystem after a call is placed.

Referring first to FIGS. 1-3, the alarm system is compactly mounted in ahousing 10 placed to the rear of a conventional telephone T. A cover 12is attached to the housing by screws 14, and carries a mounting bracket24 which extends substantially horizontally between the arms 28 of thetelephone cradle. The bracket is attached at its forward end to a hinge22 which extends laterally beyond the arms 28 into ears 26 forsupporting the housing 10 removably on the telephone cradle. A lever 18is pivotally mounted by the hinge, extending rearwardly under thetelephone receiver 30 to the housing. The lever 18 terminates in a hookportion 20, extending freely through a slot 16 in the cover 12 into theinterior of the housing. The receiver may be raised from its cradle to aposition 30 high enough to complete a telephone circuit, by raising thelever to position 18' (FIG. 2), and lowered back onto the cradle by areverse movement of the lever. The raised position 18 is high enough tocomplete the telephone circuit, but the receiver is not raised above theforward arms 28 so that it could become displaced from alignment withthe cradle.

The housing 10 also mounts a test pushbutton 32, and a connector meansor receptacle 36 for a cable 38 extending to one or more conditiondetectors or transducers which will be described further hereinafter,but are illustrated by a temperature sensor bulb TS. A contactmicrophone CM is attached to the telephone by a clip (not shown), and isconnected to the system by a cable 42. A series of holes 34 are formedin the cover plate 12, and a speaker S (not shown in FIGS. 1-3) ismounted on the reverse face of the plate behind these holes.

Referring now more particularly to FIGS. 2-5, a motor M is mountedwithin the housing on brackets 46 attached to a baseplate 70. The motordrives a speed-reducing gear train including a worm 48, worm gear 50 andpinion 52 fixed on a common shaft 51, and a gear 54 fixed on a shaft 60.A crank 55 having two axially extending pins 56 is mounted on the shaft60, and cooperates with the arms of a star wheel 58 fixed on a shaft 62,to form an escapement or intermittent lost-motion drive. The star wheelis turned in intermittent steps in the direction shown by the arrows inFIG. 4.

Retrograde motion of the star wheel 58 is prevented by a lever 64,forming a pawl 65 biased toward engagement with the star wheel by atension spring 66. The lever is pivoted on one of several posts 63 whichmount a cover plate 68 on the baseplate 70. As the star wheel is turnedby engagement with one of the pins 56, the lever 64 is deflected toallow the oncoming arm of the star wheel to pass; subsequent release ofthe star wheel by the driving pin 56 is accompanied by latching of thestar wheel by the pawl 65.

The star wheel 58 and shaft 62 drive a commutator disc C, and a cammeans comprising a crank 67 carrying a drive pin 72. The hook portion 20of the lever 18 rests on the pin 72, so that a half-revolution of thecrank 67 raises the lever to the position l8 (FIG. 2) to lift thereceiver 30 from its cradle, and the completion of a full revolutionlowers it to hang up the receiver.

The commutator C has a conductive surface which is interrupted over anarcuate sector by an insulating portion 74. The conductive portion iselectrically connected by the drive train to a ground lead of the motorM. A conductive brush 76 rests in frictional sliding engagement againstthe face of the commutator disc, and is mounted by an insulating support78 on a platform 75 attached to the plate 68. The commutator provides aswitch means for interrupting operation of the motor M after a singlerevolution of the shaft 62 and the crank 67, during which one cycle ofraising the receiver 30 and returning it to its cradle is carried out.

The housing 10 accommodates a casing 79 (see FIG. 2) mounting batteriesB for energizing the system; it also encloses a loudspeaker S and aswitching circuit AS, which are shown in the circuit diagram of FIG. 6.

The alarm system may be connected to any desired number of conditiondetectors, each including switch means which remain open while thedetected condition remains within normal limits, but which are closed bya transducer in response to an abnormal deviation. By way ofillustration, three detectors are shown. These include atemperature-responsive switch TS incorporating a thermostatic bimetallicelement or expansion bulb; a power relay contact lPR which is held openby a power relay PR connected across power supply lines unless a powerfailure occurs, permitting the contact to close; and a fuel supplyswitch FS which is closed by a float 86 in a fuel tank 84 in the eventthat the fuel level 88 decreases below a predetermined height.

The switches TS, lPR and F8 are connected in parallel, and are connectedas a group by the cable38 and the connector means or receptacle 36 inseries relation to the remainder of the circuit. A junction box 80 isschematically illustrated as a convenient means for connecting thevarious detectors. Pilot lamps (not shown) for each detector may beincorporated in this box as a ready means for identifying which of thevarious detectors has located an abnormal condition, after an alarmsignal has been delivered.

The batteries B are connected through the connector receptacle 36 inseries with the loudspeaker S and the motor M. The test pushbutton 32 isconnected in parallel with the receptacle 36 so that the operation ofthe system and the condition of the batteries can be checked when thedetected conditions are normal. A resistor R1 shunts a portion of theavailable power from the speaker to the motor. The motor circuit iscompleted alternatively through the commutator C and its brush 76, orthrough a silicon-controlled transistor rectifier SCR, which isincorporated in a microphone-amplifier circuit AS.

THe contact microphone CM attached to the telephone T responds to thering of the telephone bell, and its impulses are amplified by atransistor amplifier A. The rectifier SCR and amplifier A are coupled ina conventional manner by resistors R2, R3, R4, and R5, and a capacitorC1, in such a manner that the amplified calling signal switches therectifier to a conductive state.

ln the event that any one of the detector switches TS, lPR, or F5 isclosed when a call is placed to the telephone, a circuit through themotor M and speaker S is completed through the rectifier SCR. Thecircuit remains incomplete, even though one of the detector switches isclosed, until the receipt of a call renders the rectifier conductive.

As the motor is initially energized, the commutator switch C isrotationally positioned as shown, with the brush 76 engaging theinsulated portion 74; but as the motor rotates the commutator, the brushengages the conductive surface. The resulting closing of the commutatorswitch bypasses the motor circuit through the commutator to thebatteries, and short circuits the amplifier circuit AS, thereby causingthe rectifier SCR to assume a nonconductive state. The motor continuesto operate until the commutator has rotated one full revolution, and thebush 76 once again encounters the insulated portion. This breaks themotor speaker circuit and shuts the device off, ready for the next cycleof operation.

As the motor turns the commutator and the crank 67 through onerevolution, the telephone receiver is lifted to complete the telephonecircuit, while the loudspeaker is energized to produce an audible signalgenerated by the electrical noise of the motor. This signal is clearlyaudible to the calling person. The receiver is then returned to itscradle as the commutator C shuts off the system.

The delay in completing the telephone circuit which is occasioned by theescapement or lost-motion drive previously described, results in acharacteristic time sequence of response which is easily recognized bythe caller. We prefer to arrange the mechanical drive to hold thereceiver off its cradle for about 3 to 5 seconds, long enough to enablethe caller to clearly recognize the alarm signal. in use with telephonesin party line systems, an increased delay in lifting the receiver can beincorporated into the mechanical drive, or by adding a time-delay relay,of sufficient duration to enable all parties to receive their callswithout interference from the alarm system.

While the conditions detected by the switches TS, lPR, and FS remainnormal, there is no current flow from the batteries B. Ringing of thetelephone draws no current because the amplifier switch AS isdisconnected. When any of the detector switches are closed by anabnormal condition, a minute current flows through the amplifier switch,but this is too small to affect the power of the batteries unless itpersists for a long period of time. Substantial power is drained fromthe batteries only during the short interval when an alarm signal isbeing delivered to a caller, so that a long battery service life isobtained.

A microphone CM of the contact type, used in combination with aloudspeaker S, is preferred because it averts recycling of the system inresponse to the feedback of its own alarm signal. A buzzer signal mightproduce a recycling feedback response even in a contact microphone. Buta sound microphone can be used in combination with a speaker or buzzer,or a contact microphone can be used with a buzzer, if an appropriatetime-delay relay is added to the system to discontinue its operationafter a predetermined interval.

A system is shown in H0. 7 which incorporates a soundsensitivemicrophone and time-delay means for preventing recycling by an alarmsignal generated by the system. A single normally open conditiondetector switch TS is shown by way of illustration, connected in serieswith the battery B by the connector receptacle 36. A normally closedcontact 1TR2 of a time-delay relay TR2 connects the battery in serieswith a normally open microphone-amplifier switch AS, which is operableby a sound microphone SM is response to the ring of the telephone T.

In the event that an abnormal condition closes the switch TS, and a callis placed to the telephone, the resulting closure of the switch ASenergizes a locking relay LR. This relay closes a normally open relaycontact lLR, energizing timedelay relays TRl and TR2. The relay TRlcloses its normally open contact lTRl only after a predeterminedinterval, which serves to delay the operation of the alarm system.Closure of the contact lTRl energizes a speaker S and a solenoid RS,which is mechanically connected to raise the receiver of the telephone Tand thus complete the telephone circuit to deliver the alarm signal tothe caller.

The relay TR2 times for a period which is longer than that of the relayTRl by an interval which determines the length of operation of the alarmsystem. At the end of this period, this relay opens its normally closedcontact lTR2 and deenergizes the system, causing the solenoid RS toreturn the telephone receiver to its cradle. The feedback of the alarmsignal to the microphone SM does not cause the system to recycle becausethe amplifier switch AS is disconnected. Deenergization of the lockingrelay LR by the contact 1TR2 prepares the system for an ensuing cycle,instituted by another call to the telephone, by deenergizing the relaysTR] and TR2.

It should be noted that the time-delay relays TR] and TR2 may beincorporated into the circuit of FIG. 6 if desired, the former tointroduce a fixed delay in responding to a call to the associatedtelephone, and the latter to prevent recycling when used with a soundmicrophone or the combination of a contact microphone and a buzzer.

What I claim is:

1. An alarm system for use with a telephone, comprising circuit meansincluding first and second switch means, said first switch meansincluding a first transducer responsive to an abnormal physicalcondition to activate said first switch means, said second switch meansincluding a second transducer operable in response to a call to thetelephone to activate said second switch means, said circuit meansfurther including means constructed and arranged for producing a signalthrough the telephone system, said first and second switch meansconnecting said circuit means to actuate said signalproducing means onlywhen both of said switch means are concurrently in an activated state,whereby said alarm system remains inactive during the existence of anabnormal physical condition until a call is placed to the telephone, andremains inactive during the placing of a call to the telephone unless anabnormal physical condition exists.

2. An alarm system as recited in claim 1, said signal-producing meanscomprising motive means connected for activation only by closure of bothof said switch means, and being constructed and arranged for raising thetelephone receiver from its cradle in response to placement of a call tothe telephone, and for lowering the telephone receiver to its cradleafter an interval to terminate the call.

3. An alarm system as recited in claim 2, said motive means includingcam means driven thereby, and a pivoted lever constructed and arrangedfor raising and lowering a telephone receiver when pivotally oscillated,said cam means engaging said lever to raise and lower the telephonereceiver in response to a predetermined cycle of motion of said motivemeans.

4. An alarm system as recited in claim 3, said motive means furtherincluding lost-motion means drivingly connecting said motive means withsaid cam means and constructed and arranged to raise and lower saidlever in intermittent steps and to maintain the position of the leverduring intervals between the steps of its movement.

5. An alarm system as recited in claim 2, including bracket meansadapted to extend between the cradle and receiver of an associatedtelephone and having laterally extending ears for retaining said bracketmeans in place on the cradle, said motive means including a leverpivoted on said bracket means and constructed and arranged for raisingand lowering the receiver when pivotally oscillated.

6. An alarm system as recited in claim 2, said circuit means including athird normally closed switch means operable by said motive means andconstructed and arranged to be opened by a predetermined motion of saidmotive means corresponding to a cycle of raising and lowering of thetelephone receiver, thereby to deenergize said circuit means.

7. An alarm system as recited in claim 6, said second switch means beingconstructed and arranged to close in response to operation of saidsecond transducer by placement of a call to the telephone, and to reopenwhen short circuited;

said third switch means comprising a commutator and brush connected inparallel with said second switch means, said commutator and brush beingarranged to form electrical contact during operation of said motivemeans and subsequent to closure of said first and second switch means,thereby to short circuit and reopen said second switch means whilemaintaining said circuit means energized, said commutator and brushbeing arranged to be opened by completion of said predetermined motionto deenergize said circuit means and deactivate said motive means.

8. An alarm system as recited in claim 1, said second transducercomprising a contact microphone sensitive to vibration and insensitiveto sound transmitted through the atmosphere, said transducer beingadapted for attachment to the telephone for response to ringing of itsbell.

9. An alarm system as recited in claim 1, said circuit means including atimed third switch means constructed and arranged to open said circuitmeans after a predetermined interval of activation of saidsignal-producing means initiated by placing a call to the telephone,whereby recycling of the alarm system is not instigated by operation ofsaid signal-producing means.

10. An alarm system as recited in claim 9, said second transducercomprising a sound-sensitive microphone.

11. An alarm system as recited in claim 1, said circuit means includinga time-delay switch means constructed and arranged to close said circuitmeans only after a predetermined interval following placement of a callto the telephone, whereby operation of said signal-producing means isdelayed and follows the placement of a call to the telephone by saidinterval.

12. An alarm system as recited in claim I, said first and second switchmeans being connected in series in said circuit means and being normallyopen, activation of said switch means closing said circuit means toactuate said signalproducing means.

13. An alarm system as recited in claim 1, said signalproducing meansincluding sound-producing means for delivering an audible signal throughthe telephone.

14. An alarm system for use with a telephone, comprising circuit meansincluding connector means adapted for connection by first switch meanshaving a first transducer responsive to an abnormal physical conditionto activate said first switch means, said circuit means including secondswitch means adapted for activation by a second transducer in responseto a call to the associated telephone, said circuit means furtherincluding means constructed and arranged for producing a signal throughthe telephone system, said first and second switch means connecting saidcircuit means to actuate said signal-producing means only when saidconnector means is connected in said circuit means by activation of saidfirst switch means and said second switch means is concurrentlyactivated, whereby said alarm system remains inactive during theexistence of an abnormal physical condition until a call is placed tothe telephone, and remains inactive during the placement of a call tothe telephone unless an abnormal physical condition exists.

1. An alarm system for use with a telephone, comprising circuit meansincluding first and second switch means, said first switch meansincluding a first transducer responsive to an abnormal physicalcondition to activate said first switch means, said second switch meansincluding a second trAnsducer operable in response to a call to thetelephone to activate said second switch means, said circuit meansfurther including means constructed and arranged for producing a signalthrough the telephone system, said first and second switch meansconnecting said circuit means to actuate said signal-producing meansonly when both of said switch means are concurrently in an activatedstate, whereby said alarm system remains inactive during the existenceof an abnormal physical condition until a call is placed to thetelephone, and remains inactive during the placing of a call to thetelephone unless an abnormal physical condition exists.
 2. An alarmsystem as recited in claim 1, said signal-producing means comprisingmotive means connected for activation only by closure of both of saidswitch means, and being constructed and arranged for raising thetelephone receiver from its cradle in response to placement of a call tothe telephone, and for lowering the telephone receiver to its cradleafter an interval to terminate the call.
 3. An alarm system as recitedin claim 2, said motive means including cam means driven thereby, and apivoted lever constructed and arranged for raising and lowering atelephone receiver when pivotally oscillated, said cam means engagingsaid lever to raise and lower the telephone receiver in response to apredetermined cycle of motion of said motive means.
 4. An alarm systemas recited in claim 3, said motive means further including lost-motionmeans drivingly connecting said motive means with said cam means andconstructed and arranged to raise and lower said lever in intermittentsteps and to maintain the position of the lever during intervals betweenthe steps of its movement.
 5. An alarm system as recited in claim 2,including bracket means adapted to extend between the cradle andreceiver of an associated telephone and having laterally extending earsfor retaining said bracket means in place on the cradle, said motivemeans including a lever pivoted on said bracket means and constructedand arranged for raising and lowering the receiver when pivotallyoscillated.
 6. An alarm system as recited in claim 2, said circuit meansincluding a third normally closed switch means operable by said motivemeans and constructed and arranged to be opened by a predeterminedmotion of said motive means corresponding to a cycle of raising andlowering of the telephone receiver, thereby to deenergize said circuitmeans.
 7. An alarm system as recited in claim 6, said second switchmeans being constructed and arranged to close in response to operationof said second transducer by placement of a call to the telephone, andto reopen when short circuited; said third switch means comprising acommutator and brush connected in parallel with said second switchmeans, said commutator and brush being arranged to form electricalcontact during operation of said motive means and subsequent to closureof said first and second switch means, thereby to short circuit andreopen said second switch means while maintaining said circuit meansenergized, said commutator and brush being arranged to be opened bycompletion of said predetermined motion to deenergize said circuit meansand deactivate said motive means.
 8. An alarm system as recited in claim1, said second transducer comprising a contact microphone sensitive tovibration and insensitive to sound transmitted through the atmosphere,said transducer being adapted for attachment to the telephone forresponse to ringing of its bell.
 9. An alarm system as recited in claim1, said circuit means including a timed third switch means constructedand arranged to open said circuit means after a predetermined intervalof activation of said signal-producing means initiated by placing a callto the telephone, whereby recycling of the alarm system is notinstigated by operation of said signal-producing means.
 10. An alarmsystem as recited in claim 9, said second transducer comprising asound-sensItive microphone.
 11. An alarm system as recited in claim 1,said circuit means including a time-delay switch means constructed andarranged to close said circuit means only after a predetermined intervalfollowing placement of a call to the telephone, whereby operation ofsaid signal-producing means is delayed and follows the placement of acall to the telephone by said interval.
 12. An alarm system as recitedin claim 1, said first and second switch means being connected in seriesin said circuit means and being normally open, activation of said switchmeans closing said circuit means to actuate said signal-producing means.13. An alarm system as recited in claim 1, said signal-producing meansincluding sound-producing means for delivering an audible signal throughthe telephone.
 14. An alarm system for use with a telephone, comprisingcircuit means including connector means adapted for connection by firstswitch means having a first transducer responsive to an abnormalphysical condition to activate said first switch means, said circuitmeans including second switch means adapted for activation by a secondtransducer in response to a call to the associated telephone, saidcircuit means further including means constructed and arranged forproducing a signal through the telephone system, said first and secondswitch means connecting said circuit means to actuate saidsignal-producing means only when said connector means is connected insaid circuit means by activation of said first switch means and saidsecond switch means is concurrently activated, whereby said alarm systemremains inactive during the existence of an abnormal physical conditionuntil a call is placed to the telephone, and remains inactive during theplacement of a call to the telephone unless an abnormal physicalcondition exists.